1 post per category

I'm currently working on www.deserter.be/wordpress and have installed the Tank theme.

Now when you click on the DeserteR tab (it's a band btw) you can see that in that tab i have 4 other ones. It's meant as subpages.
Now when you click on deserter it shows all the post i put in for the band. But i only want to show 1 post so i can put the info about the band there when you click on deserter.

Is there a way to do it?
Thanks a lot!